Electro-optical device and method of manufacture thereof, and electronic instrument

ABSTRACT

An electro-optical device comprises first and second substrates ( 10, 20 ) disposed facing each other, an interconnect ( 14 ) formed on the surface of the first substrate ( 10 ) opposing the second substrate ( 20 ), and a conductive member ( 40 ) passing through the second substrate ( 20 ) and reaching both surfaces of the second substrate ( 20 ), and the conductive member ( 40 ) and interconnect ( 14 ) are electrically connected between the first and second substrates ( 10, 20 ).

TECHNICAL FIELD

The present invention relates to an electro-optical device and method ofmanufacture thereof, and to an electronic instrument.

BACKGROUND OF ART

A liquid crystal panel has two transparent substrates, with a liquidcrystal sealed between them. In a conventional liquid crystal panel, onetransparent substrate has a projection which projects laterally beyondthe other transparent substrate. Transparent electrodes are connected tointerconnects extending over this projection to be gathered toward theend. The ends of the interconnects form external terminals aligned in astraight line. On the projection is fixed the end of a flexibleinterconnect substrate. At the end of the flexible interconnectsubstrate, interconnect pattern connection terminals are exposed, andthe connection terminals are electrically connected to the externalterminals formed on the projection of the transparent substrate.

The flexible interconnect substrate is bent from the end connected tothe projection to the rear of the liquid crystal panel, and is disposedon the rear of the liquid crystal panel. Therefore, the bent portion ofthe flexible interconnect substrate projects on the outside of theprojection, and therefore a display device equipped with the liquidcrystal panel is made more bulky. With the increasing miniaturization ofelectronic instruments in recent years (in particular theminiaturization of portable devices such as portable telephones), thedemand for miniaturization of electro-optical devices has grown strongerand stronger.

The present invention solves the above problem, and has as its objectthe provision of an electro-optical device capable of miniaturizationand method of manufacture thereof, and of an electronic instrument.

DISCLOSURE OF INVENTION

(1) The electro-optical device of the present invention comprises:

first and second substrates disposed to oppose each other;

an interconnect formed on (above) a surface of the first substrateopposing the second substrate; and

a conductive member provided to pass through the second substrate,

wherein the conductive member and the interconnect are electricallyconnected between the first and second substrates.

According to the present invention, the conductive member to which theinterconnect is electrically connected extends as far as both surfacesof the second substrate. As a result, for the interconnect positionedbetween the opposing first and second substrates, an electricalconnection through the conductive member from the surface of the secondsubstrate opposite to the first substrate can be obtained. Moreover,since the conductive member and interconnect are electrically connectedbetween the first and second substrates, the electro-optical device canbe miniaturized.

(2) This electro-optical device may further comprise a conductordisposed on (above) an opposite side of the second substrate from thefirst substrate, and

the conductor may electrically connected to the conductive member.

By means of this, through the conductor and conductive member, anelectrical connection to the interconnect can be achieved.

(3) This electro-optical device may further comprise an integratedcircuit chip disposed on (above) the an integrated circuit chip disposedon an opposite side of the second substrate from the first substrate,and

the conductor may be electrically connected to the integrated circuitchip.

By means of this, through the conductor and conductive member, anelectrical connection between the integrated circuit chip and theinterconnect can be achieved.

(4) In this electro-optical device:

a plurality of the interconnects may be formed, and

a plurality of the conductive members electrically connected to theplurality of interconnects may be provided.

(5) In this electro-optical device:

the plurality of conductive members may be arranged in a zigzag.

By means of this, even if the pitch of the plurality of interconnects issmall, the pitch of the plurality of conductive members can be madelarger.

(6) In this electro-optical device:

the conductive member may be formed on (above) a part of the secondsubstrate which overlaps with the first substrate.

By means of this, since the conductive member can be provided within thearea of the outer form of the first or second substrate, theelectro-optical device can be further miniaturized.

(7) In this electro-optical device:

a part of the second substrate may project beyond the regioncorresponding to the first substrate, and

the conductive member may be formed on (above) the projected part of thesecond substrate.

The present invention is not such as to prevent such an embodiment.

(8) In this electro-optical device:

an integrated circuit chip may be mounted on the projected part of thesecond substrate.

In this way, the projecting part of the second substrate may be used.

(9) In this electro-optical device:

the first and second substrates may be adhered together by a sealant,and

the conductive member may be formed closer to end of the secondsubstrate than the sealant.

In this configuration, the conductive member can be observed fromoutside of the sealant.

(10) In this electro-optical device:

the first and second substrates may be adhered together by a sealant;and

the conductive member may be formed toward the center portion of thesecond substrate from the sealant.

By means of this, the conductive member is protected by the sealant.

(11) In this electro-optical device:

the first and second substrates may be adhered together by a sealant,and

the conductive member may be formed on (above) a portion of the secondsubstrate which overlaps with the sealant.

By means of this, since the area in which the sealant is provided andthe area in which the conductive member is provided overlap each other,the electro-optical device can be further miniaturized.

(12) In this electro-optical device:

the sealant may be an anisotropic conductive adhesive material.

(13) The electronic instrument of the present invention comprises theabove described electro-optical device.

According to the present invention, since the electro-optical device canbe miniaturized, the electronic instrument can also be miniaturized.

(14) The method of manufacture of an electro-optical device of thepresent invention comprises disposing a first substrate on (above) whichan interconnect is formed and a second substrate through which aconductive member is provided so as to oppose each other with theinterconnect on (above) inside between the first and second substrates,and electrically connecting the conductive member and the interconnectbetween the first and second substrates.

According to the present invention, for the interconnect positionedbetween the opposing first and second substrates, an electricalconnection through the conductive member from the surface of the secondsubstrate opposite to the first substrate can be obtained. Moreover,since the conductive member and interconnect are electrically connectedbetween the first and second substrates, a compact electro-opticaldevice can be obtained.

(15) In this method of manufacture of an electro-optical device:

through hole may be formed in the second substrate, and the conductivemember may be provided in the through hole.

By means of this, since the conductive member is provided within theouter form of the second substrate, the conductive member can bedisposed not to protrude outside the second substrate.

(16) In this method of manufacture of an electro-optical device:

a hole smaller than the through hole may be first formed, then the holeis enlarged to form the through hole.

By means of this, the hole can be formed with less energy than theformation of the through hole, and having formed the hole in advance,the through hole can be formed with less energy.

(17) In this method of manufacture of an electro-optical device:

a depression may be formed in a position for forming the through hole,and the depression is used for positioning in forming the hole.

By means of this, the position of forming the through hole can beassured by the depression, and therefore the through hole can be formedwith accurate positioning.

(18) In this method of manufacture of an electro-optical device:

the hole may be formed by a laser beam, and enlarged by wet etching.

By means of this, the through hole can be formed easily. Even if theinner surface of the hole formed by the laser beam are rough, throughhole with smooth inner walls can be formed since they are enlarged bywet etching.

BRIEF DESCRIPTION OF DRAWINGS

FIG. 1 illustrates a first embodiment of a liquid crystal panel to whichthe present invention is applied, and is a section along the line I—I inFIG. 3.

FIG. 2 illustrates the first embodiment of a liquid crystal panel towhich the present invention is applied, and is a sectional view alongthe line II—II in FIG. 3.

FIG. 3 illustrates the first embodiment of a liquid crystal panel towhich the present invention is applied.

FIG. 4 illustrates a modification of the first embodiment of a liquidcrystal panel to which the present invention is applied.

FIG. 5 illustrates a second embodiment of a liquid crystal panel towhich the present invention is applied.

FIG. 6 illustrates a third embodiment of a liquid crystal panel to whichthe present invention is applied.

FIG. 7 illustrates a fourth embodiment of a liquid crystal panel towhich the present invention is applied.

FIG. 8 illustrates the fourth embodiment of a liquid crystal panel towhich the present invention is applied.

FIG. 9 illustrates a fifth embodiment of a liquid crystal panel to whichthe present invention is applied.

FIG. 10 illustrates the fifth embodiment of a liquid crystal panel towhich the present invention is applied.

FIG. 11 illustrates a sixth embodiment of a liquid crystal panel towhich the present invention is applied.

FIG. 12 illustrates a seventh embodiment of a liquid crystal panel towhich the present invention is applied.

FIG. 13 illustrates an eighth embodiment of a liquid crystal panel towhich the present invention is applied.

FIG. 14 illustrates the eighth embodiment of a liquid crystal panel towhich the present invention is applied.

FIG. 15 illustrates a ninth embodiment of a liquid crystal panel towhich the present invention is applied.

FIG. 16 illustrates a tenth embodiment of a liquid crystal panel towhich the present invention is applied.

FIG. 17 shows an electronic instrument having an electro-optical deviceto which the present invention is applied.

FIG. 18 shows an electronic instrument having an electro-optical deviceto which the present invention is applied.

FIG. 19 shows an electronic instrument having an electro-optical deviceto which the present invention is applied.

BEST MODE FOR CARRYING OUT THE INVENTION

Next, embodiments of the electro-optical device according to the presentinvention are described with reference to the attached drawings. Anexample of an electro-optical device is an electro-optical panel. Anelectro-optical panel is equipped with an electro-optical substancesandwiched between panel substrates. The electro-optical panelconstitutes the display device of an electronic instrument. Examples ofan electro-optical panel include liquid crystal panels, electroluminancepanels, and plasma display panels.

First Embodiment

FIGS. 1 and 2 are enlarged sectional views showing the construction ofthe peripheral portion of this embodiment of a liquid crystal panel, andFIG. 3 is a schematic plan view of this embodiment of the liquid crystalpanel. FIG. 1 is a section along the line I—I shown in FIG. 3, and FIG.2 is a section along the line II—II shown in FIG. 3.

This embodiment of a liquid crystal panel comprises oppositely disposedfirst and second substrates 10 and 20. Of the first and secondsubstrates 10 and 20, at least one (and in this embodiment both) isformed of a transparent substrate such as glass.

On one surface of the first substrate 10 is formed a plurality ofelectrodes 12 and a plurality of interconnects 14. Between theelectrodes 12 and electrodes 22 described below, a voltage is applied toa liquid crystal 32. That is to say, the electrodes 12 include portionswhich apply a voltage to the liquid crystal 32. When light passesthrough the first substrate 10, the electrodes 12 are transparentelectrodes, formed of for example ITO (Indium Tin Oxide). The pluralityof electrodes 12 are formed in stripe form. The interconnects 14 areelectrically connected to the electrodes 12. At least over theelectrodes 12 (and in this embodiment, over the electrodes 12 andinterconnects 14), is formed an orienting film 16. On the other surfaceof the first substrate 10 is provided a polarizer 18.

On one surface of the second substrate 20 is formed a plurality ofelectrodes 22 and a plurality of interconnects 24. Between theelectrodes 22 and the electrodes 12 mentioned above, a voltage isapplied to the liquid crystal 32. That is to say, the electrodes 22include portions which apply a voltage to the liquid crystal 32. Whenlight passes through the second substrate 20, the electrodes 22 aretransparent electrodes, formed of for example ITO (Indium Tin Oxide).The plurality of electrodes 22 are formed in stripe form. Theinterconnects 24 are electrically connected to the electrodes 22.

In the second substrate 20, as shown in FIGS. 1 and 2, is formed aplurality of through holes (or through pores) 21. The through holes 21are formed in for example one row on the end of the second substrate 20.The number of the through holes 21 formed may be equal to the totalnumber of the interconnects 14 and 24. Some of the interconnects 14 and24 are disposed to reach positions overlapping with some of the throughholes 21. The parts of the plurality of interconnects 14 and 24overlapping with the through holes 21, and the plurality of throughholes 21 are formed at approximately the same pitch (for example a pitchof approximately 100 μm). The width of the interconnects 14 and 24 andthe size of the through holes 21 (the diameter if the hole is circular)may be approximately equal (for example approximately 30 μm diameter).

For each of the through holes 21 a conductive member 40 is provided. Theconductive member 40 is formed of a conductive material such as a metalor a conductive paste. The conductive member 40 is provided to passthrough the second substrate 20, and can enable electrical connectionbetween the two surfaces of the second substrate 20. That is to say, bymeans of the conductive material 40 provided in the through holes 21, anelectrical connection is constituted. The conductive member 40 may be alayer formed on the inner wall of the through holes 21 to form an open“through hole” or as with the through holes 21 shown in FIGS. 1 and 2may be filled in. If the conductive member 40 is provided in the throughholes 21, it is not necessary to cover the side of the conductive member40 or to protect it.

Even though on the second substrate 20 are provided an orienting film26, polarizer 28, reflector 29, and so on, electrical connection of twosurfaces of the second substrate 20 can be achieved by means of theconductive member 40. For example, as shown in FIGS. 1 and 2, on onesurface of the second substrate 20 the orienting film 26 may be providedto avoid the region in which the conductive member 40 is provided.Alternatively, as a variant, holes communicating with the through holes21 may be formed in the orienting film 26. On the other surface of thesecond substrate 20, as shown in FIGS. 1 and 2, holes communicating withthe through holes 21 may be formed in the polarizer 28 and reflector 29.Alternatively, as a modification, the polarizer 28 and reflector 29 maybe provided to avoid the region in which conductive member 40 isprovided.

The conductive member 40 may be formed to be flush with surroundingmembers, or may be formed so as to project beyond the surroundingmembers, or may be formed so as to be recessed with respect to thesurrounding members. For example, in FIGS. 1 and 2, the conductivemember 40 is formed flush with the surface of the second substrate 20 onwhich the interconnects 24 are formed, but it may equally project fromthis surface, or may be recessed with respect to this surface. Theconductive member 40, in FIGS. 1 and 2, is formed to project beyond thereflector 29, but may equally be formed to be flush with the reflector29, or may be formed to be recessed with respect to the reflector 29.

It should be noted that in order to provide the conductive member 40 isit sufficient that there be a path reaching both surfaces of the secondsubstrate 20 (inner and outer surfaces or front and rear surfaces). Forexample, in the end of the second substrate 20 a cutout (for example agroove formed in the side surface) may be formed and the conductivemember 40 may be provided by this cutout.

On the second substrate 20, each of the interconnects 24 is connected tosome conductive member 40. Each of the interconnects 14 formed on thefirst substrate 10 is connected to some conductive member 40, and thisis described below.

On the second substrate 20, at least over the electrodes 22 (and in thisembodiment, over the electrodes 22 and interconnects 24), the orientingfilm 26 is formed. On the other surface of the second substrate 20, thepolarizer 28 is provided.

This embodiment of a liquid crystal panel is a reflective type, and onthe outside of the polarizer 28 provided on one substrate (for examplethe second substrate 20), the reflector 29 is provided. As amodification, the electrodes 22 may be formed of a material (for examplealuminum) that reflects light, and the reflector 29 may be omitted. Inthis case, of the electrodes 22, regions between the portions used toapply a voltage to the liquid crystal 32 may be covered with alight-blocking material (a material opaque to light). Alternatively,without providing a light-blocking material, a backlight may be providedon the rear surface of the substrate (a semitransmitting-reflective typeof liquid crystal panel). Alternatively, the electrodes 12 and 22 may beformed as transparent electrodes, and a backlight may be provided on therear surface of the substrate (transmitting type of liquid crystalpanel).

The first and second substrates 10 and 20 are opposed so that theelectrodes 12 and 22 are in matrix form. The first and second substrates10 and 20 are disposed spaced apart (for example with a spacer not shownin the drawings interposed). The surface of the first substrate 10 onwhich the electrodes 12 are formed and the surface of the secondsubstrate 20 on which the electrodes 22 are formed are opposed. That isto say, the electrodes 12 and 22 and interconnects 14 and 24 aredisposed on the opposing inner surfaces of the first and secondsubstrates 10 and 20.

In a passive matrix type of liquid crystal panel, either of theelectrodes 12 and 22 (for example the electrodes 12) are signalelectrodes, and the other (for example the electrodes 22) are scanelectrodes. In an active matrix type of liquid crystal panel, either ofthe electrodes 12 and 22 (for example the electrodes 12) include pixelelectrodes, and the other (for example the electrodes 22) are commonelectrodes. The pixel electrodes are the portions which apply a voltageto the liquid crystal 32.

As shown in FIG. 2, the interconnects 14 and the conductive member 40are electrically connected to the conductive member 40. To provide thiselectrical connection, a vertical conductive member 42 is providedbetween the first and second substrates 10 and 20. For the verticalconductive member 42, a conductive paste (for example conductiveparticles (for example resin spheres the outer surface of which iscovered with a conductor such as Cr, Ni, or the like) introduced into aresin) may be used. As the conductive paste is preferably used anultraviolet-cured resin or the like which can be optically cured withoutthe application of heat to cure.

According to this embodiment, the interconnects 14 are formed on thesurface of the first substrate 10 opposing the second substrate 20, andthe conductive member 40 is provided so as to be exposed on bothsurfaces of the second substrate 20 (for example passing through thesecond substrate 20). As a result, from the surface of the secondsubstrate 20 opposite to that of the first substrate 10, an electricalconnection can be obtained with the interconnects 14 formed on the firstsubstrate 10. Moreover, the vertical conductive member 42 providing theelectrical connection between the interconnects 14 and the conductivemember 40 is provided between the first and second substrates 10 and 20.Therefore, the electro-optical device (in this embodiment, a liquidcrystal panel) can be miniaturized.

According to this embodiment, a plurality of the conductive members(connection portions) 40 are arranged along the outer periphery of thesecond substrate 20, and therefore not only is the effect on theinternal construction of the electro-optical device (liquid crystalpanel) reduced, but also the area of the second substrate 20 can bereduced. In particular, by arranging the plurality of conductive members40 in a single row (or in a straight line form), the region required forthe formation of the plurality of conductive members 40 can be reduced.

In this embodiment, the conductive members 40 are formed in a portion ofthe second substrate 20 overlapping with the first substrate 10. As aresult, since the conductive members 40 are provided within the outerform of the first and second substrates 10 and 20, in this respect also,the electro-optical device (in this embodiment, a liquid crystal panel)can be miniaturized.

It should be noted that in FIGS. 2 and 3, the number of the verticalconductive members 42 and through holes 21, and the number and form ofthe electrodes 12 and 22 and interconnects 14 and 24 are schematic, andshow a simplification of an actual liquid crystal panel.

In this embodiment, the first and second substrates 10 and 20 areadhered together by a sealant 30 and seal member 34. The sealant 30 andseal member 34 are of, for example, a resin, and both may be of the samematerial. The sealant 30 and seal member 34 are provided so as tosurround the center portion of the first and second substrates 10 and 20(for example as a frame). It should be noted that in the assembly of theliquid crystal panel, the substrates 10 and 20 are adhered together withthe sealant 30 interposed in a partial incomplete frame form, and thenafter filling with the liquid crystal 32 through the opening in thesealant 30, this opening is closed with the seal member 34.

Inside the first and second substrates 10 and 20 the liquid crystal 32being an electro-optical substance is sealed. The liquid crystal 32 issealed within a region defined by the sealant 30 and seal member 34.

In this embodiment, as shown in FIG. 3, the sealant 30 passes inside theconductive member 40 electrically connected to the interconnects 14, andpasses over the conductive member 40 electrically connected to theinterconnects 24.

In more detail, the sealant 30 is disposed on the inside of the firstand second substrates 10 and 20 from the vertical conductive member 42.In other words, the conductive member 40 connected to the interconnects14 formed on the first substrate 10 is positioned closer to the end ofthe second substrate 20 than the sealant 30. Therefore, theinterconnects 14 formed on the first substrate 10 pass over the sealant30, and are brought out outside the sealant 30.

On the other hand, the sealant 30 is provided in a position to overlapwith the conductive members 40 connected to the interconnects 24 formedon the second substrate 20. Therefore, the interconnects 24 formed onthe second substrate 20 extend below the sealant 30. Since the throughholes 21 formed to correspond to the interconnects 24 are formedpositioned below the sealant 30, it is possible to eliminate the regionoutside the sealant 30.

Alternatively, as a modification, as shown in FIG. 4, a sealant 50 andseal member 34 may be formed in a rectangle, and conductive members 40provided on the outside of the sealant 50.

On the surface of the second substrate 20 opposite to the firstsubstrate 10, a conductor 60 is electrically connected to the conductivemember 40. It should be noted that the conductor 60 may be connected toboth the conductive members 40 electrically connected to theinterconnects 14 formed on the first substrate 10 and the conductivemembers 40 electrically connected to the interconnects 24 formed on thesecond substrate 20.

The conductor 60 is an interconnect pattern formed on a substrate (forexample, a flexible substrate) 62. The conductor 60 (and the substrate62) are disposed on the side of the second substrate 20 opposite to thefirst substrate 10. By means of the conductor 60 and substrate 62 theinterconnect substrate (for example a flexible interconnect substrate)is constituted. On the interconnect substrate an integrated circuit chip(for example a semiconductor chip) 60 is mounted, and the integratedcircuit chip 64 is electrically connected to the conductor 60. Theintegrated circuit chip 64 includes a liquid crystal panel drivecircuit. The integrated circuit chip 64 is disposed on the side of thesecond substrate 20 opposite to the first substrate 10. Furthermore, toprevent malfunction caused by light the integrated circuit chip 64 maybe covered by a light blocking film 66.

According to this embodiment, the conductor 60 is electrically connectedto the interconnects 14 formed on the first substrate 10 with theconductive member 40 and vertical conductive member 42 interposed. Sincethe conductive member 40 passes through the second substrate 20, theconductor 60 need not be brought out on the side of the second substrate20. Therefore, the space occupied by the conductor 60 is small, andconsequently the device in which the liquid crystal panel is installedcan be miniaturized.

This embodiment of a liquid crystal panel is constructed as describedabove, and the method of manufacture thereof is now described.

A first substrate 10 on which the interconnects 14 are formed, and asecond substrate 20 through which the conductive members 40 pass and onwhich the interconnects 24 are formed are taken. In this embodiment, theconductive member 40 is provided within through holes 40 formed in thesecond substrate 20. The method of formation of the through holes 21 isnow described.

On for example the second substrate 20, a mask is provided in a patterncorresponding to the through holes 21. Then blast processing (sandblasting, scribing) or etching processing (wet etching by hydrofluoricacid or a mixture hydrofluoric acid and sulfuric acid or dry etching byhalogen gas or the like) is applied, or ultrasound processing or laserprocessing is applied whereby the through holes 21 are formed.

Alternatively, holes smaller than the through holes 21 can be previouslyformed, and holes enlarged to provide the through holes 21. By means ofthis, the holes can be formed with less energy than the through holes21, and by preforming the holes, the energy for forming the throughholes 21 can be reduced.

To form the holes, a laser (for example a YAG laser or C02 laser) can beused. The laser beam may be directed at one surface of the secondsubstrate 20 to provide the holes, or the laser bean may be directedfrom both sides of the second substrate 20 (either sequentially orsimultaneously). If the laser beam is directed from both sides, theinfluence on the second substrate 20 is reduced.

It should be noted that a depression may be formed beforehand in theposition of forming the through holes 21, and by means of thedepression, positioning may be carried out to provide the holes. Bymeans of this, the position of forming the through holes 21 can be madecertain by means of the depression, and the through holes 21 can beformed in precise positions. The depression can be formed by etching(wet etching or dry etching).

When enlarging the holes to form the through holes 21, wet etching canbe applied. As an etchant is used, for example, an aqueous solution of amixture of hydrofluoric acid and ammonium fluoride (bufferedhydrofluoric acid). By means of this, the through holes 21 can be easilyformed. Even if the inner walls of holes formed by a laser beam arerough, since they are enlarged by wet etching, through holes 21 withsmooth inner walls can be formed.

To provide the through holes 21 with the conductive member 40, platingmay be applied. For example, a metal layer may be formed on the innerwalls through of the holes 21 by electroless plating, and an open“through hole” may be provided. Alternatively, the interior of thethrough holes 21 may be filled with a metal by plating. More concretely,by closing one of the openings on both sides of the through holes 21with a metal plate, and supplying a plating fluid from the opening onthe opposite side, a metal pillar may be provided by electrolessplating. Alternatively, the through holes 21 may be filled with a moltenmetal (molten solder or the like), or a conductive resin (conductivepaste). Alternatively, sputtering, vapor deposition, or the like may beused to deposit a conductor within the through holes 21. Alternatively,a reactive gas such as tungsten carbonyl, molybdenum carbonyl, or thelike may be supplied, while a laser beam is directed into the throughholes 21, to deposit tungsten, molybdenum, or the like on the innersurface of the through holes 21 (laser CVD). Alternatively, aninterconnect may be passed through the through holes 21.

When the first and second substrates 10 and 20 are ready, the first andsecond substrates 10 and 20 are fixed opposing with the interconnects 14and 24 disposed on the inside. Between the first and second substrates10 and 20, for example the vertical conductive member 42 is provided.The vertical conductive member 42 is provided to connect theinterconnects 14 and the conductive member 40 formed on the secondsubstrate 20. The step of providing the vertical conductive member 42may be carried out before fixing the first and second substrates 10 and20, or if possible may be carried out afterwards. In this way, theconductive member 40 and the interconnects 14 can be electricallyconnected.

Second Embodiment

FIG. 5 shows a second embodiment to which the present invention isapplied. This embodiment of a liquid crystal panel comprises the firstand second substrates 10 and 20 described in the first embodiment, andon the second substrate 20 at least one conductor 70 is provided. InFIG. 5 one conductor 70 is shown, but a plurality of conductors 70 maybe provided. The conductor 70 is a bump (bump electrode), and can beformed of a brazing material (for example solder) or other metal. As themethod of forming the conductor 70, solder balls may be mounted.Alternatively, the conductor 70 may be provided by depositing a metal byplating on, for example, the conductive member 40.

The conductor 70 is provided on the surface of the second substrate 20opposite to the first substrate 10, and is electrically connected to theconductive member 40. In the example shown in FIG. 5, the conductor 70is provided on the conductive member 40, but as a modification thereof,an interconnect (conductor) may be brought out from the conductivemember 40, and the conductor 70 may be provided in a different positionfrom the conductive member 40. For example, a plurality of conductivemembers 40 may be disposed to form a plurality of rows and a pluralityof columns (two-dimensionally).

In this embodiment, since the conductor 70 is formed on the outersurface of the second substrate 20, the liquid crystal panel can be indirect electrical contact with connection terminals formed on thesurface of a circuit board or the like. This construction is appropriatewhen using a panel support to which the liquid crystal panel is fixed.In this case, the liquid crystal panel is fixed so. that the conductor70 is pressed against a connection terminal formed as a pad on thesurface of the circuit board installed within the electronic instrument.

It should be noted that if the conductor 70 is pressed against anotherconductor which is not fixed with respect to the liquid crystal panel,then the conductive member 40 may be constructed by means of aconductive resilient member, for example a conductive rubber or thelike. By means of the fact that the conductor 70 (terminal portion) isformed at the extremity of the resilient member, the stress applied tothe liquid crystal panel can be reduced.

Third Embodiment

FIG. 6 shows a third embodiment to which the present invention isapplied. This embodiment of a liquid crystal panel comprises the firstand second substrates 10 and 20 described in the first embodiment.

In this embodiment, an integrated circuit chip 80 is mounted on thesecond substrate 20. The details of the integrated circuit chip 64described in the first embodiment apply to the integrated circuit chip80. The integrated circuit chip 80 is electrically connected to theconductive member 40 on the surface of the second substrate 20 oppositeto the first substrate 10. In the example shown in FIG. 6, theelectrodes (bumps) of the integrated circuit chip 80 are bonded to theconductive member 40, but the electrodes and conductive member 40 may beelectrically connected by a conductor such as an interconnect or thelike.

On the second substrate 20, on the surface opposite to the firstsubstrate 10, a conductor 82 such as an interconnect (or an interconnectpattern) or the like is formed, and the conductor 82 is electricallyconnected to the integrated circuit chip 80 (more precisely to theelectrodes (bumps) thereof). The conductor 82 may be electricallyconnected to the interconnect substrate (conductor 60 and substrate 62)described in the first embodiment.

According to this embodiment, an integrated circuit chip 80 can bemounted on the liquid crystal panel. Moreover, since it is not necessaryto provide a projection on the second substrate 20 projecting from thefirst substrate 10, the liquid crystal panel can be constructed to becompact.

Fourth Embodiment

FIGS. 7 and 8 show a fourth embodiment to which the present invention isapplied. This embodiment of a liquid crystal panel comprises the firstand second substrates 10 and 20 described in the first embodiment.

In this embodiment, a conductive member 90 passing through the secondsubstrate 20 is formed on the second substrate 20, on the central side(inside) from a sealant 92. The details of the conductive member 40described in the first embodiment apply to the conductive member 90,except for its position. A vertical conductive member 94 is also formedon the second substrate 20 in the center part from (inside) the sealant92. The details of the vertical conductive member 94 described in thefirst embodiment apply to the vertical conductive member 94 except forits position.

According to this embodiment, the interconnects 14 and 24 (see FIGS. 1to 3) can be formed without passing between the sealant 92 and the firstand second substrates 10 and 20. The region of the first and secondsubstrates 10 and 20 outside the sealant 92 can be made smaller. As aresult, without reducing the size of the display area, the liquidcrystal panel can be made more compact.

Fifth Embodiment

FIGS. 9 and 10 show a fifth embodiment to which the present invention isapplied. This embodiment of a liquid crystal panel comprises the firstand second substrates 10 and 20 described in the first embodiment.

In this embodiment, the conductive member 40 passing through the secondsubstrate 20 is formed in a position overlapping with a sealant 100. Asthe sealant 100 may be used an anisotropic conductive adhesive materialsuch as an anisotropic conductive film (ACF), anisotropic conductivepaste (ACP), or the like.

In this case, on at least either of the interconnects 14 and conductivemember 40 (both, in the example shown in FIG. 9) are formed bumps 102.It should be noted that the conductive member 40 may be caused toproject from the surface of the second substrate 20, and part of theconductive member 40 may form bumps 102. Since the conductive particlesof the anisotropic conductive adhesive material are present between thebumps 102, electrical connection between the interconnects 14 and theconductive member 40 can be achieved. In this case, the bumps 102 andconductive particles form a vertical conductive member.

Sixth Embodiment

FIG. 11 shows a sixth embodiment to which the present invention isapplied. This embodiment of a liquid crystal panel comprises first andsecond panels 110 and 120.

On a first substrate 110 is formed a plurality of electrodes 112 and aplurality of interconnects 114. The plurality of electrodes 112 is in astripe form, and the interconnects 114 are formed in the same directionas the electrodes 112. The interconnects 114 extend to the end of oneside of the first substrate 110 which is of rectangular form.

On a second substrate 120 a plurality of electrodes 122 and a pluralityof interconnects 124 is formed. The plurality of electrodes 122 is instripe form, and the interconnects 124 are formed in the-same directionas the electrodes 122. The interconnects 124 extend to the end of oneside of the second substrate 120 which is of rectangular form.

The first and second substrates 110 and 120 are disposed so that theelectrodes 112 and 122 are in matrix form. The end of the firstsubstrate 110 to which the interconnects 114 are brought out (the righthand side in FIG. 11) and the end of the second substrate 120 to whichthe interconnects 124 are brought out (the top side in FIG. 11) arepositioned as adjacent ends separated by a corner.

Then on the second substrate 120, a plurality of conductive members 140is provided. The conductive members 140 are the same as the conductivemember 40 described in the first embodiment. However, in thisembodiment, the conductive members 140 are formed on the ends adjacentends of the second substrate 120 separated by a corner (the right andtop ends in FIG. 11). The conductive members 140 formed on one end (theright hand side in FIG. 11) are electrically connected through avertical conductive member 142 to the interconnects 114 formed on thefirst substrate 110. The conductive members 140 formed on another end(the top in FIG. 11) are electrically connected to the interconnects 124formed on the second substrate 120.

Then on the inside of the conductive members 140, a sealant 130 isprovided. This point is the same as in the aspect shown in FIG. 4. Inother respects, the content described in the first embodiment applies.

Seventh Embodiment

FIG. 12 shows a seventh embodiment to which the present invention isapplied. This embodiment of a liquid crystal panel comprises first andsecond substrates 150 and 160. On the first substrate 150, electrodes(not shown in the drawings) and interconnects 154 (the same content asthe electrodes 12 and interconnects 14 described in the first embodimentapplies) are formed. On the second substrate 160, electrodes not shownin the drawings and interconnects (the same content as the electrodes 22and interconnects 24 described in the first embodiment applies) areformed.

On the second substrate 160, a plurality of conductive members 170 isprovided. In this embodiment, the plurality of conductive members 170 isarranged in a plurality of rows. Of the conductive members 170 alignedin a particular row, corresponding to the region between a pair of theconductive members 170, one of an adjacent row of conductive members 170is aligned. In other words, the plurality of conductive members 170 isarranged in a zigzag. Except for this point, the details of theconductive member 40 described in the first embodiment applies to theconductive members 170.

On the second substrate 160, an interconnect 162 electrically connectedto the conductive members 170 is formed. The interconnect 162 is formedon the inside of the second substrate 160 from the conductive members170. The interconnect 162 is electrically connected to the interconnects154 formed on the first substrate 150 between the first and secondsubstrates 150 and 160. For this electrical connection, as described inthe fifth embodiment, an anisotropic conductive adhesive material may beused as a sealant 180, and bumps 172 may be provided.

In this embodiment, since the conductive members 170 are in zigzag form,the pitch of the conductive members 170 can be made large. Therefore,even for a finely dimensioned panel, a large number of conductivemembers 170 can easily be formed in a confined space. Since theconductive members 170 can be made large (of large diameter), theconduction resistance can be reduced.

Eighth Embodiment

FIGS. 13 and 14 shown an eighth embodiment to which the presentinvention is applied. This embodiment of a liquid crystal panelcomprises the first substrate 10 described in the first embodiment and asecond substrate 200. The end of the second substrate 200 is disposed toproject beyond the end of the first substrate 10. The overall form ofthe second substrate 200 may be larger than the first substrate 10, orfirst and second substrates 10 and 200 of the same size may be used witha relative displacement.

Between the first and second substrates 10 and 200, a verticalconductive member 42 as described in the first embodiment is provided.On the second substrate 200 an interconnect 202 is formed. Theinterconnect 202 is electrically connected to the vertical conductivemember 42, and is formed to reach as far as the part of the secondsubstrate 200 which projects beyond the first substrate 10. On the partof the second substrate 200 which projects beyond the first substrate10, an integrated circuit chip 204 (to which the details of theintegrated circuit chip 80 shown in FIG. 6 apply) is mounted. Theinterconnect 202 is electrically connected to the integrated circuitchip 204.

On the part of the second substrate 200 which projects beyond the firstsubstrate 10, the conductive member 40 described in the first embodimentis provided. The conductive member 40 is electrically connected to theinterconnects 14 formed on the first substrate 10. In this embodiment,an interconnect 206 formed on the second substrate 200 is electricallyconnected to the conductive member 40. The interconnect 206 iselectrically connected to the integrated circuit chip 204. Therefore,the conductive member 40 is electrically connected through theinterconnect 206, integrated circuit chip 204, interconnect 202, andvertical conductive member 42, to the interconnects 14 formed on thefirst substrate 10.

This embodiment of a liquid crystal panel has a COG (Chip On Glass)construction. The end of the second substrate 200 is provided with aprojection, but this projection need only be sufficiently large for theintegrated circuit chip 204 to be mounted. Since it is not necessary tobring an interconnect substrate out on the outside of the integratedcircuit chip 204, the amount of projection can be greatly reducedcompared with a conventional projection.

In place of the integrated circuit chip 204, an integrated circuit suchas a driver circuit or the like may be directly created on the surfaceof the second substrate 200, and formed integrally with theinterconnects 202 and 206. In this case, the integrated circuit may beformed immediately under the sealant 30 so as to underlie it. At thistime, the conductive member 40 may also be formed in a position directlyunderneath the sealant 30 to underlie it. In this case, for theintegrated circuit chip 204 and the integrated circuit, the number ofinput and output terminals for is fewer in number than the number ofinterconnects brought out from the display region. As a result, there isthe additional advantage that the number of conductive members(connections) 40 can be reduced, and the manufacturing cost can bereduced.

Ninth Embodiment

FIG. 15 shows a ninth embodiment to which the present invention isapplied. This embodiment of a liquid crystal panel is an active matrixtype liquid crystal panel. That is to say, active elements such as thinfilm transistors (TFT) are formed for each pixel region arranged in amatrix. A first substrate 210 equipped with electrodes not shown in thedrawings and a second substrate 220 on which active elements are formedare disposed opposing each other. The first and second substrates 210and 220 are adhered together with a sealant 230 interposed, and betweenthem a liquid crystal (not shown in the drawings) is sealed.

On the second substrate 220 are formed the active elements, pixelelectrodes which apply a voltage through the active elements, and scanlines and data lines connected to the active elements. The secondsubstrate 220 has a larger area than the first substrate 210, and in theregion outside the sealant 230, a scan line drive circuit 222 and dataline drive circuit 224 are formed. The scan line drive circuit 222 iselectrically connected to the scan lines by interconnects not shown inthe drawings, and the data line drive circuit 224 is electricallyconnected to the data lines by interconnects not shown in the drawings.

On the first substrate 210 are formed a plurality of electrodes(transparent electrodes) and interconnects, not shown in the drawings.The interconnects, are electrically connected to conductive members 240of the second substrate 220 through vertical conductive members 242formed for example at the four corners of the first substrate 210. Inthis embodiment, below the scan line drive circuit 222 and data linedrive circuit 224, a plurality of conductive members 240 is provided.The details of the conductive member 40 described in the firstembodiment apply to the conductive members 240. The vertical conductivemembers 242 and conductive members 240 are electrically connected byinterconnects.

On the inside of the sealant 230 on the first substrate 210 a lightblocking film 212 is formed in the form of a frame. The light blockingfilm 212 is formed of a black ink constituting a black matrix or a thinfilm of metal such as chromium or the like, and defines the outer limitsof the display region of the liquid crystal panel (the viewing area).

To the formation of the above described active elements, scan line drivecircuit 222 and data line drive circuit 224, and the like comprising theintegrated circuit is preferable applied technology to form siliconpolycrystals in a low temperature process (low temperature polysilicontechnology). By means of this, the liquid crystal panel with internaldriver circuit can be fabricated at low cost. Since the integratedcircuit can be formed below the sealant 230, the liquid crystal panelcan be miniaturized.

Tenth Embodiment

FIG. 16 shows a tenth embodiment to which the present invention isapplied. In this embodiment is described a liquid crystal panel modulein which a liquid crystal panel to which the present invention isapplied is incorporated. The liquid crystal panel module is mounted on acircuit board installed within an electronic instrument.

The liquid crystal panel module comprises a liquid crystal panel 310 anda panel support 320 formed of synthetic resin on which this is mounted.The panel support 320 can be constituted of a transparent resin such asan acrylic resin or the like, and has a planar light-conductive plate321, and a frame 322 supporting the end of the light-conductive plate321. A reflective layer 324 is formed by adhering a white resin film tothe rear surface of the light-conductive plate 321.

The liquid crystal panel 310 is that described in the above embodiments.The liquid crystal panel 310 is fixed, for example by being adhered bydouble-sided adhesive tape or the like to the surface of thelight-conductive plate 321. The frame 322 formed on the periphery of thelight-conductive plate 321 functions to position the liquid crystalpanel 10 and to protect the end of the liquid crystal panel 310.

On a flexible interconnect substrate 330 is mounted an integratedcircuit chip 333 such as a driver IC or the like, and the integratedcircuit chip 333 is covered by a light blocking film 334.

The panel support 320 is fixed to a circuit board not shown in thedrawings within the electronic instrument. A light source 317 such as alight emitting diode or the like commonly mounted on the circuit boardis opposed to the side surface of the light-conductive plate 321, andlight is conducted from the side surface into the light-conductive plate321. When light enters the light-conductive plate 321, it is emittedalmost uniformly from the surface of the light-conductive plate 321toward the liquid crystal panel 310. The light is passed through theliquid crystal panel 310, allowing optical control (for example aparticular display).

Other Embodiments

The electro-optical device (for example a liquid crystal panel) to whichthe present invention is applied can be used in a variety of electronicinstruments, such as the personal computer 1000 shown in FIG. 17, theportable telephone shown in FIG. 18, a portable data display terminal, aclock, and the like. In particular, by using the above described liquidcrystal panel in a portable device, the display can be made morecompact, and therefore the instrument as a whole can be made morecompact.

Next a projection type display device (liquid crystal projector) using aliquid crystal panel to which the present invention is applied isdescribed. FIG. 19 schematically illustrates the optical system of theprojection type display device of this embodiment.

A projection type display device 400 comprises an illumination opticalsystem equipped with a light source 402 and a plurality of integratorlenses, a color separation optical system (light supply optical system)equipped with a plurality of dichroic mirrors and the like, a liquidcrystal light valve (liquid crystal optical shutter array) 404corresponding to red color (for red color), a liquid crystal light valve(liquid crystal optical shutter array) 406 corresponding to green color(for green color), a liquid crystal light valve (liquid crystal opticalshutter array) 408 corresponding to blue color (for blue color), adichroic prism (color combining optical system) 414 having formed adichroic mirror surface 410 reflecting only red light and a dichroicmirror surface 412 reflecting only blue light, and a projection lens(projection optical system) 416.

The illumination optical system comprises integrator lenses 418 and 420.The color separation optical system comprises mirrors 422, 424, and 426,a dichroic mirror 428 which reflects blue light and green light (allowsonly red light to pass), a dichroic mirror 430 which reflects greenlight only, a dichroic mirror 432 which reflects only blue light (or amirror which reflects blue light), and condenser lenses 434, 436, 438,440, and 442.

The liquid crystal light valve 406 includes the liquid crystal panel towhich the present invention is applied. To the entry surface of theliquid crystal panel (the surface on which a microlens substrate ispositioned, in other words the opposite side to the dichroic prism 21) afirst polarizer (not shown in the drawings) is bonded, and to theemission surface of the liquid crystal panel (the surface opposing themicrolens substrate, that is to say, the side of the dichroic prism 21)a second polarizer (not shown in the drawings) is bonded. The liquidcrystal light valves 404 and 408 are also constructed in the same way asthe liquid crystal light valve 406. The liquid crystal panel equippedwith these liquid crystal light valves 404, 406, and 408 is connected torespective drive circuits not shown in the drawings.

With the projection type display device 400, the dichroic prism 414 andprojection lens 416 constitute an optical system 444. This opticalsystem 444 and the liquid crystal light valves 404, 406, and 408installed in fixed positions with respect to the dichroic prism 414constitute a display unit 446.

Next the operation of the projection type display device 400 isdescribed.

White light (a white light beam) emitted by the light source 402 passesthrough the integrator lenses 418 and 420. The strength (intensitydistribution) of this white light is rendered uniform by the integratorlenses 418 and 420.

The white light that has passed through the integrator lenses 418 and420 is reflected by the mirror 422, and of the reflected light the bluelight (B) and green light (G) are each reflected by the dichroic mirror428, while the red light (R) passes through the dichroic mirror 428.

The red light which has passed through the dichroic mirror 428 isreflected by the mirror 424, and this reflected light is collimated bythe condenser lens 434, and then impinges on the red color liquidcrystal light valve 404.

Of the blue light and green light reflected by the dichroic mirror 428,the green light is reflected by the dichroic mirror 430, and the bluelight passes through the dichroic mirror 430.

The green light reflected by the dichroic mirror 430 is collimated bythe condenser lens 436, and then impinges on the green color liquidcrystal light valve 406.

The blue light which has passed through the dichroic mirror 430 isreflected by the dichroic mirror (or mirror) 432, and this reflectedlight is reflected by the mirror 426. The blue light is collimated bythe condenser lenses 438, 440, and 442, and then impinges on the bluecolor liquid crystal light valve 408.

In this way, the white light emitted by the light source 402 undergoescolor separation into the three primary colors red, green, and blue bythe color separation optical system, and is supplied to and impinges onthe corresponding liquid crystal light valves.

At this point the pixels of the liquid crystal panel of the liquidcrystal light valve 404 (the thin film transistors and the pixelelectrodes connected thereto) are subjected to switching (on/off)control by a drive circuit (drive means) operating based on an imagesignal for red, that is to say, are modulated.

Similarly, the green light and blue light impinges on respective liquidcrystal light valves 406 and 408, and is modulated by the respectiveliquid crystal panels, thus forming a green image and a blue image. Atthis point the pixels of the liquid crystal panel of the liquid crystallight valve 406 are subjected to switching control by a drive circuitoperating based on an image signal for green, and the pixels of theliquid crystal panel of the liquid crystal light valve 408 are subjectedto switching control by a drive circuit operating based on an imagesignal for blue.

In this way the red light, green light, and blue light is modulated bythe respective liquid crystal light valves 404, 406, and 408 to createrespectively a red image, green image and blue image.

The red image formed by the liquid crystal light valve 404, that is tosay, the red light from the liquid crystal light valve 404, enters thedichroic prism 414 from the surface 448, is reflected by the dichroicmirror surface 410, passes through the dichroic mirror surface 412, andis emitted from the emission surface 450.

The green image formed by the liquid crystal light valve 406, that is tosay, the green light from the liquid crystal light valve 406, enters thedichroic prism 414 from the surface 452, passes through the dichroicmirror surfaces 410 and 412, and is emitted from the emission surface450.

The blue image formed by the liquid crystal light valve 408, that is tosay, the blue light from the liquid crystal light valve 408, enters thedichroic prism 414 from the surface 456, is reflected by the dichroicmirror surface 412, passes through the dichroic mirror surface 410, andis emitted from the emission surface 450.

In this way, the light of different colors from the liquid crystal lightvalves 404, 406, and 408, that is to say, the images formed by theliquid crystal light valves 404, 406, and 408, are combined by thedichroic prism 414, and in this way a full-color image is formed. Thisimage is projected (enlarged projection) on a screen 454 installed in asuitable position, by means of a projection lens 416.

What is claimed is:
 1. An electro-optical device comprising: first andsecond substrates disposed to oppose each other; an interconnect formedon a surface of the first substrate opposing the second substrate; aconductive member provided to pass through the second substrate; aconductor disposed on an opposite side of the second substrate from thefirst substrate, the conductor electrically connected to the conductivemember, the conductor extending to overlap with the interconnect; and avertical conductive member provided between the interconnect and theconductive member, the vertical conductive member provided on theconductive member, wherein the conductive member and the interconnectare electrically connected between the first and second substrates. 2.The electro-optical device as defined in claim 1, further comprising anintegrated circuit chip disposed on an opposite side of the secondsubstrate from the first substrate, wherein the conductor iselectrically connected to the integrated circuit chip.
 3. Theelectro-optical device as defined in claim 1, wherein a plurality of theinterconnects are formed, and wherein a plurality of the conductivemembers electrically connected to the plurality of interconnects areprovided.
 4. The electro-optical device as defined in claim 3, whereinthe plurality of conductive members are arranged in a zigzag.
 5. Theelectro-optical device as defined in claim 1, wherein the conductivemember is formed on a part of the second substrate which overlaps withthe first substrate.
 6. The electro-optical device as defined in claim1, wherein the first and second substrates are adhered together by asealant, and wherein the conductive member is formed on a portion of thesecond substrate which overlaps with the sealant.
 7. The electro-opticaldevice as defined in claim 6, wherein the sealant is an anisotropicconductive adhesive material.
 8. An electronic instrument comprising theelectro-optical device as defined in claim
 1. 9. An electro-opticaldevice comprising: first and second substrates disposed to oppose eachother, the second substrate having a penetrating hole formed therein; aninterconnect formed on the surface of the first substrate opposing thesecond substrate; a conductive member provided in the penetrating hole;and a vertical conductive member provided between the interconnect andthe conductive member, the vertical conductive member provided on theconductive member, wherein the conductive member and the interconnectare electrically connected between the first and second substrates,wherein the first and second substrates are adhered together by asealant, and wherein the conductive member is formed closer to an end ofthe second substrate than the sealant.
 10. An electronic instrumentcomprising the electro-optical device as defined in claim
 9. 11. Anelectro-optical device comprising: first and second substrates disposedto oppose each other; an interconnect formed on a surface of the firstsubstrate opposing the second substrate; a conductive member provided topass through the second substrate; and a vertical conductive memberprovided between the interconnect and the conductive member, thevertical conductive member provided on the conductive member, whereinthe conductive member and the interconnect are electrically connectedbetween the first and second substrates, wherein the first and secondsubstrates are adhered together by a sealant, and wherein the conductivemember is formed closer to a center of the substrate than the sealant.12. An electronic instrument comprising the electro-optical device asdefined in claim 11.